But, without doubt, there are few places more risky to your career than the office Christmas party.

Despite the fact the work Christmas party is often held at a location that is not on company property (ie a bar) the occasion is seen as being "in the course of employment", reports Wales Online.

Owen John, senior associate with law firm Darwin Gray, said: "Conduct which takes place at a Christmas party, even if that Christmas party was held off-site, will be treated the same as if it was carried out at the workplace itself."

And while that's bad news for the employee, it also means an employer can be held liable for their employee’s actions as a result of "off-duty" conduct on such occasions.

"It is possible for an employer to take disciplinary action against employees who display bad behaviour during or even after a Christmas party," said Nia Cooper, partner at law firm Capital Law.

"Such conduct is likely to fall within the ‘course of employment’ and so can be treated as if the conduct were committed whilst at work."

Of course, not everything's going to get you fired. But these are 10 things you probably shouldn't do.

1. Get (very) drunk

This unnamed Plymouth University student was caught napping in the toilet at a bar during what appears to be a heavy night on the tiles in 2014.

It's a party, so you can expect a lot of people to get a bit tipsy. But there is a big difference between having a few and dancing on the bar or starting a fight.

As long as you don't do anything that crosses the legal line then the worst punishment you will likely have is feeling embarrassed for weeks.

If the company puts on a free bar employees might feel that they can not be held responsible for all of their actions. But that is debatable.

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Ms Cooper recalls an example where three employees successfully argued that their dismissals for drunken behaviour at a work training event were unfair, a relevant factor being that the employer had provided a free bar, "thereby condoning their behaviour".

But Mr John believes that a free bar is irrelevant.

"If the employee commits an act of gross misconduct, an employer can discipline that employee, and if is sufficiently serious, potentially dismiss that employee. The fact that the employer put on a free bar will be no defence for the employee," he said.

2. Ask for a pay rise

There is a time and a place to negotiate a change in your pay, the Christmas party is not it. A change in contract if a delicate negotiation and pay rises would need to be backed up by facts and figures to show why the change in pay is deserved.

Where will your Christmas party be this year?

Drunken slurring about how you're the best employee to your boss while spilling your drink will have the opposite effect.

3. Invite friends when there is a free bar

The free bar is a gift from the employer to the employees - if your mates turn up this will make you very unpopular.

Free bar! Weyyyyyyyyyyyy!

It might be hard for an employer to prove you invited them, so may not face disciplinary action. But you won't have won any friends with your colleagues.

4. Make sexual advances to a colleague

This could lead to big trouble for the employee and the employer.

"An employer may be ultimately responsible for the actions of its employees at a Christmas party, just as it may be responsible for the actions of its employees in the workplace," says Mr John.

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"Therefore, by way of example, if Employee A sexually harasses Employee B at a Christmas party, Employee B could potentially bring legal action against the employer (who will ultimately be responsible for the action of Employee A) as well as Employee A."

5. Not turn up or leave early

Attending the party is not as easy for some as it is for others. Some employees might want to avoid the event for religious reasons or they might find it difficult to get childcare for the night. They might just not want to go.

"In a multi-cultural society, we have to consider whether or not the concept of the Christmas party is outdated," says Ian Dawson, head of employment at corporate solicitors Shulmans.

Thinking of sneaking off early? Don't.

"Few of those employees who don’t celebrate Christmas themselves will raise objections to the annual office bash, generally because they’re too polite and don’t want to be seen as a Grinch. They’re left making excuses as to why they can’t attend and thus lose out on the treat provided for others."

6. Gossip or bad mouth colleagues

A few drinks might make people more talkative, but putting down colleagues or gossiping will not go down well. You don't know if the person you are talking will repeat your rumours or opinions and it could lead to awkward conversations when you sober up and have to face people in the office.

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7. Fight

"Fighting constitutes gross misconduct, which should be dealt with formally under the company’s disciplinary procedures," says Ms Cooper.

"Although fighting will most likely justify dismissal, it is imperative that employers carry out as thorough investigation as possible. In recent cases, a failure to identify who ‘threw the first punch’ and resulting inconsistent treatment of those involved has led to findings of unfair dismissal.

"It is important to take pre-emptive action to ensure that employees are aware of their obligations prior to the event. That way, the employer limits their exposure to any unauthorised conduct which an employee may then go on to commit."

8. Talk work all night

Do this and you might find you have a lot of very short conversations. The Christmas party is a chance to talk with colleagues, but not about work. You don't want to be known as Boring Dave for the next 12 months.

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9. Overload your plate from the buffet

'It's just wafer thin'

The food is for everyone. So make sure it will last the night. If you don't think there will be enough food on offer then eat something before you go. You want to have something to eat, especially if you're drinking, but you don't want be the person at fault for why someone else hasn't got any pizza.